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מאמרים קשורים
Discoveries from a Near-infrared Proper Motion Survey Using Multi-epoch Two Micron All-Sky Survey Data
We have conducted a 4030 deg2 near-infrared proper motionsurvey using multi-epoch data from the Two Micron All-Sky Survey(2MASS). We find 2778 proper motion candidates, 647 of which are notlisted in SIMBAD. After comparison to Digitized Sky Survey images, wefind that 107 of our proper motion candidates lack counterparts at B, R,and I bands and are thus 2MASS-only detections. We present results ofspectroscopic follow-up of 188 targets that include the infrared-onlysources along with selected optical-counterpart sources with faintreduced proper motions or interesting colors. We also establish a set ofnear-infrared spectroscopic standards with which to anchor near-infraredclassifications for our objects. Among the discoveries are six youngfield brown dwarfs, five "red L" dwarfs, three L-type subdwarfs, twelveM-type subdwarfs, eight "blue L" dwarfs, and several T dwarfs. Wefurther refine the definitions of these exotic classes to aid futureidentification of similar objects. We examine their kinematics and findthat both the "blue L" and "red L" dwarfs appear to be drawn from arelatively old population. This survey provides a glimpse of the kindsof research that will be possible through time-domain infrared projectssuch as the UKIDSS Large Area Survey, various VISTA surveys, and WISE,and also through z- or y-band enabled, multi-epoch surveys such asPan-STARRS and LSST.Some of the spectroscopic data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership amongthe California Institute of Technology, the University of California,and the National Aeronautics and Space Administration. The Observatorywas made possible by the generous financial support of the W. M. KeckFoundation. Other spectroscopic data were collected at the SubaruTelescope, which is operated by the National Astronomical Observatory ofJapan.
| Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
| A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)
The LSPM catalog is a comprehensive list of 61,977 stars north of theJ2000 celestial equator that have proper motions larger than 0.15"yr-1 (local-background-stars frame). The catalog has beengenerated primarily as a result of our systematic search for high propermotion stars in the Digitized Sky Surveys using our SUPERBLINK software.At brighter magnitudes, the catalog incorporates stars and data from theTycho-2 Catalogue and also, to a lesser extent, from the All-SkyCompiled Catalogue of 2.5 million stars. The LSPM catalog considerablyexpands over the old Luyten (Luyten Half-Second [LHS] and New LuytenTwo-Tenths [NLTT]) catalogs, superseding them for northern declinations.Positions are given with an accuracy of <~100 mas at the 2000.0epoch, and absolute proper motions are given with an accuracy of ~8 masyr-1. Corrections to the local-background-stars propermotions have been calculated, and absolute proper motions in theextragalactic frame are given. Whenever available, we also give opticalBT and VT magnitudes (from Tycho-2, ASCC-2.5),photographic BJ, RF, and IN magnitudes(from USNO-B1 catalog), and infrared J, H, and Ks magnitudes(from 2MASS). We also provide an estimated V magnitude and V-J color fornearly all catalog entries, useful for initial classification of thestars. The catalog is estimated to be over 99% complete at high Galacticlatitudes (|b|>15deg) and over 90% complete at lowGalactic latitudes (|b|>15deg), down to a magnitudeV=19.0, and has a limiting magnitude V=21.0. All the northern starslisted in the LHS and NLTT catalogs have been reidentified, and theirpositions, proper motions, and magnitudes reevaluated. The catalog alsolists a large number of completely new objects, which promise to expandvery significantly the census of red dwarfs, subdwarfs, and white dwarfsin the vicinity of the Sun.Based on data mining of the Digitized Sky Surveys (DSSs), developed andoperated by the Catalogs and Surveys Branch of the Space TelescopeScience Institute (STScI), Baltimore.Developed with support from the National Science Foundation (NSF), aspart of the NASA/NSF NStars program.
| Improved Astrometry and Photometry for the Luyten Catalog. II. Faint Stars and the Revised Catalog
We complete construction of a catalog containing improved astrometry andnew optical/infrared photometry for the vast majority of NLTT starslying in the overlap of regions covered by POSS I and by the secondincremental Two Micron All Sky Survey (2MASS) release, approximately 44%of the sky. The epoch 2000 positions are typically accurate to 130 mas,the proper motions to 5.5 mas yr-1, and the V-J colors to0.25 mag. Relative proper motions of binary components are measured to 3mas yr-1. The false-identification rate is ~1% for11<~V<~18 and substantially less at brighter magnitudes. Theseimprovements permit the construction of a reduced proper-motion diagramthat, for the first time, allows one to classify NLTT stars intomain-sequence (MS) stars, subdwarfs (SDs), and white dwarfs (WDs). We inturn use this diagram to analyze the properties of both our catalog andthe NLTT catalog on which it is based. In sharp contrast to popularbelief, we find that NLTT incompleteness in the plane is almostcompletely concentrated in MS stars, and that SDs and WDs are detectedalmost uniformly over the sky δ>-33deg. Our catalogwill therefore provide a powerful tool to probe these populationsstatistically, as well as to reliably identify individual SDs and WDs.
| An H-alpha survey of neglected Vyssotsky Catalog stars
Consideration is given to a significant number of Vyssotsky K- andM-dwarfs that have either no published radial velocity (71 stars), or avelocity based on a single measure (22), or with an uncertaintly greaterthan 5 km/s (19). An 'in flare' observation of Vys 250A compared to itsquiescent state, and an example of the double-lined phase of Vys 250Bare illustrated. Mean values from the observations are given in tabularform.
| Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.
| The general catalogue of trigonometric [stellar] paralaxes
Not Available
| Dwarf K and M stars of high proper motion found in a hemispheric survey
A recently completed visual/red spectral region objective-prism surveyof more than half the sky found some 2200 dwarf K and M stars ofnegligible proper motion (Stephenson, 1986). The present paper adds the1800-odd spectroscopically identified dwarfs that did prove to havesignificant proper motions. About half of these had previous spectralclassifications of some sort, especially by Vyssotsky (1952, 1956). Forthe great majority, the present coordinates are more accurate thanprevious data. The paper includes about 50 stars with unpublishedparallaxes, likely to have parallaxes of 0.05 arcsec or more. Combiningthe present data with the first paper suggests that the number oflow-proper-motion stars in that paper was not unreasonable.
| G. P. Kuiper's spectral classifications of proper-motion stars
Spectral classifications are listed for over 3200 stars, mainly of largeproper motion, observed and classified by Kuiper during the years1937-1944 at the Yerkes and McDonald Observatories. While Kuiper himselfpublished many of his types, and while improved classifications are nowavailable for many of these stars, much of value remains. For many ofthe objects, no other spectral data exist.
| The luminosity law for late-type main-sequence stars in the solar neighborhood
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974PASP...86..697E&db_key=AST
| Catalog of Indidual Radial Velocities, 0h-12h, Measured by Astronomers of the Mount Wilson Observatory
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJS...19..387A&db_key=AST
| Photovisual magnitudes of 418 dwarf M stars and 34 parallax stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1956AJ.....61..219S&db_key=AST
| Dwarf M Stars Found Spectrophotometrically.
Abstract image available at:http://adsabs.harvard.edu/abs/1943ApJ....97..381V
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| קבוצת-כוכבים: | לינכס |
| התרוממות ימנית: | 08h34m03.63s |
| סירוב: | +42°33'30.5" |
| גודל גלוי: | 10.378 |
| תנועה נכונה: | 195.2 |
| תנועה נכונה: | -100.3 |
| B-T magnitude: | 11.726 |
| V-T magnitude: | 10.49 |
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